WO2018130495A1

WO2018130495A1 - Method for machining bevel gears using an eccentrically moved cup grinding wheel which can be dressed

Info

Publication number: WO2018130495A1
Application number: PCT/EP2018/050359
Authority: WO
Inventors: Rolf Schalaster
Original assignee: Klingelnberg Ag
Priority date: 2017-01-16
Filing date: 2018-01-08
Publication date: 2018-07-19
Also published as: JP7015312B2; EP3348354B1; US11806798B2; US20190344368A1; CN110267766B; JP2020504022A; EP3348354A1; CN110267766A

Abstract

The invention relates to a method which is carried out in a grinding machine (100) comprising the following: - a tool spindle (11) for receiving a cup grinding wheel (10), which is provided with an abrasive surface, and for rotating the cup grinding wheel (10) about a rotational axis (R1), - a dressing spindle (31) for receiving a dressing tool (30), which is designed to dress the cup grinding wheel (10), and for rotating the dressing tool (30) about a rotational axis (R3), and - a workpiece spindle (41) for receiving a bevel gear workpiece (40) and for rotating the bevel gear workpiece (40) about a rotational axis (R2), wherein the workpiece spindle (41) is provided with an eccentric drive, having the following dressing steps: a) rotating the cup grinding wheel (10) about the rotational axis (R1) of the tool spindle (11) at a first rotational speed, b) rotating the dressing tool (30) about the rotational axis (R3) of the dressing spindle (31) at a second rotational speed, and c) carrying out a dressing method in which the cup grinding wheel (10) is dressed by the dressing tool (30), wherein a determined fixed rotational speed ratio between the first rotational speed and the second rotational speed is specified during step c), and having the following machining steps which are carried out after carrying out the dressing steps: i. eccentrically rotating the cup grinding wheel (10) about the rotational axis (R1) of the tool spindle (11) at a first machining rotational speed using the eccentric drive and ii. carrying out a grinding method in which the bevel gear workpiece (40) is machined in a grinding manner using the cup grinding wheel (10).

Description

METHOD FOR PROCESSING CONE WHEELS USING AN ECCENTRICALLY MOVED, RIGGABLE

POT WHEEL

The invention relates to a method for machining bevel gears using a dressing cup grinding wheel, which is moved eccentrically.

State of the art

It is known that one can edit bevel gears using a grinding tool. Often, cup grinding wheels are used.

Mostly dressable cup grinding wheels are used. Such cup grinding wheels are dressed from time to time to extend their life and z. B. to be able to compensate for signs of wear.

In FIG. 1 schematically indicates how such a pot-shaped grinding wheel 10 can be dressed in a grinding machine 100 with a rotation-driven dressing wheel 30. In the moment shown, the dressing wheel 30 aligns the grinding wheel 10 on the outer circumference. For this purpose, the dressing wheel 30 sits outside and above the grinding wheel 10. To dress the cup grinding wheel 10 in its interior, the dressing wheel 30 is CNC-controlled in another, lying in the interior of the cup grinding wheel 10 position, brought and it is reversed direction. In Fig. 1, the dressing wheel 30 is shown in dashed lines in a position for dressing the inside of the profile 28 of the cup grinding wheel 10. The CNC control (path control) of the machine 100 transmits the required profile to the grinding wheel 10 by the dressing wheel 30 is CNC guided along the profile 18 of the grinding wheel 10. Further details about this dressing process described by way of example can be found, for example, in the patent EP2774721B1.

Only with a cup grinding wheel 10, the dimensional and dimensional accuracy is within close tolerances, a highly accurate workpiece machining can be performed. It must always be ensured that the state of the cup grinding wheel 10 is processable.

A suitably trained grinding cup 10 can, for. B. are used for discontinuous Wälzschleifen of bevel gear pieces 40, as shown in FIG. 3A. However, such a cup wheel 10 can also be used for discontinuous profile grinding (also called dip grinding) of bevel gear pieces 40, as shown in Fig. 2.

With the dip grinding only wheels can be edited. By contrast, bevel gears and ring gears can be machined with generating grinding.

In the discontinuous plunge grinding and generating grinding is about grinding processes by the item method.

When immersing the grinding wheel 10, the profile of the cup grinding wheel 10 is imaged in the material of the ring gear 40 to be produced when immersion grinding. In the in Fig. As shown in FIG. 2, the cup grinding wheel 10 has just worked on a single tooth gap 5 of the bevel gear workpiece 40.

It is known that the immersion movement of the cup grinding wheel 10 when immersion grinding and generating grinding an eccentric additional movement of the grinding wheel center point M l (M l defines the passage point of a corresponding axis of rotation through the plane of the drawing) so as to avoid grinding burn and to prevent clogging of the surface of the grinding wheel 10 with metal particles. Details of the eccentric movement of the cup wheel 10 are, for example, the schematic Fig. 3A.

By the mentioned superimposing, the cup grinding wheel center M l moves on a circular path about a center point M2 (M2 defines the passage point of a corresponding axis of rotation through the drawing plane). The radius of this circular path is referred to as Exzenterhub e and is small compared to the radius of the cup grinding wheel 10. Due to this movement, the cup grinding wheel 10 touches the workpiece 40 geometrically viewed only along a line perpendicular to the plane of FIG. 3A stands. In reality, however, due to the relative advancing movement, it is a localized area 4 along the said line in which the contact takes place. The ratio of the eccentric speed to the rotational speed of the cup grinding wheel 10 is the so-called eccentric ratio EV.

The eccentric additional movement can be done in grinding machines 100 by adjusting the eccentric EV, respectively, the eccentric speed in the form of a fixed specification.

In Fig. 3A, by way of example, the Waguri approach is shown in which a cup grinding wheel 10 rotates about the disk center point M 1 offset from the center point M2 of a wagon disk 3 by a small distance e (called Waguri eccentricity). The eccentric ratio EV is defined as the rotational speed of the eccentric divided by the rotational speed n 1 of the cup grinding wheel 10. The cup wheel 10 rotates when editing the workpiece 40 with the angular velocity col * around the center M l. The eccentric movement causes for the center M l of the cup grinding wheel 10 a circular movement about M2. This circular movement has components of motion in the x-direction and in the y-direction.

FIG. 3B shows a section along the line X1-X1 through the cup grinding wheel 10. In FIG. 3B you can see the profile 18 of the cup grinding wheel 10 recognize. The circumferential outer surface of the profile 18 is denoted by the reference numeral 18.1 and the circumferential inner surface by the reference numeral 18.2.

Due to the superimposed eccentric is achieved that a (too) large surface contact between the outer periphery 18.1 of the profile 18 of the cup grinding wheel 10 and the entire surface of the concave edge 5.1 of the workpiece 40 and between the inner periphery 18.2 of the profile 18 of the cup grinding wheel 10th and the entire surface of the convex flank 5.2 is avoided.

In otherwise constant conditions, the frequency of contact of the cup grinding wheel 10 with the tooth edge 5.1 or 5.2, the location of this contact area on the cup grinding wheel 10 and the phase position of the contact of concave and convex tooth flank 5.2, 5.1 depend on the selected eccentric EV.

If the eccentric EV = 1, then the eccentric 3 rotates once during a full rotation of the cup grinding wheel 10. The cup grinding wheel 10 thus touches the concave flank 5.1 of the tooth gap 5 (at 0 °) and once the convex flank 5.2 of the tooth gap 5 (at 180 °) once for each full revolution. The touch always takes place in the same area. If the eccentric ratio EV = 2, two contacts of the cup grinding wheel 10 with the concave edge 5.1 of the tooth gap 5 (at 0 ° and 180 °) respectively with the convex edge 5.2 of the tooth gap 5 (at 90 ° and 270 °) take place during one full revolution the cup grinding wheel 10. These degrees refer to a fixed yz coordinate system of the grinding wheel 10 and in these special cases, there is no displacement of the contact areas along the grinding wheel circumference from full rotation of the cup grinding wheel 10 to full rotation.

The eccentric ratio EV, which is given, may also be a rational number Q. A practical example is an eccentric ratio of EV = 0.7. When the cup wheel 10 performs several full turns, the contact areas continue to shift and it will eventually the entire grinding wheel circumference on the profile 18 used for grinding machining.

By the eccentric movement, an undesirably large surface contact between the cup grinding wheel 10 and the workpiece 40 can be avoided. Details on the overlay of a cyclic eccentric movement can be found, for example, in German Offenlegungsschriften DE 2721164 A and DE 2445483 A.

Practical studies have shown that rolled bevel gears, which were ground using the eccentric motion, may have a surface with optically visible shades. In addition, these components can show in operation a conspicuous noise behavior, which is due to ripples of the tooth flanks.

Therefore, the invention has for its object to provide an approach that makes it possible to avoid this unusual noise behavior.

The object is achieved according to the invention by a method according to claim 1.

The method of the invention is carried out in a grinding machine comprising:

a tool spindle for receiving a cup grinding wheel provided with an abrasive surface and for rotationally driving the cup grinding wheel about an axis of rotation,

a dressing spindle for receiving a dressing tool designed for dressing the cup grinding wheel and for rotationally driving the dressing tool about an axis of rotation,

a workpiece spindle for receiving a bevel gear workpiece and for rotationally driving the bevel gear workpiece about an axis of rotation, the workpiece spindle being provided with an eccentric drive whose eccentric ratio can be predetermined.

The method of the invention comprises in all embodiments the following dressing steps: a) rotationally driving the cup grinding wheel about the axis of rotation of the tool spindle at a first speed,

b) rotationally driving the dressing tool about the axis of rotation of the dressing spindle at a second speed,

c) performing a dressing process in which the cup grinding wheel is dressed with the dressing tool, wherein a predetermined, fixed speed ratio is specified between the first speed and the second speed during this step,

and with the following processing steps, which are carried out after the dressing steps have been carried out:

i. eccentrically rotating the cup grinding wheel about the axis of rotation of the tool spindle at a first machining speed using the eccentric drive,

i. Performing a grinding process in which the bevel gear is sanded with the cup grinding wheel.

The invention is based on a holistic approach that optimizes the interaction of the dresser during the dressing process with the cup grinding wheel and the interaction of the appropriately honed cup grinding wheel with the bevel gear. The development of this approach became possible only after other errors and inaccuracies of previous dressings and grinding operations were systematically excluded.

It has then been shown in close examination that the conditions of the dressing process can have negative effects on the grinding processing of the workpieces that have not been recognized so far.

According to the invention, therefore, the corresponding speed ratios are specially matched.

For this purpose, for example, in all embodiments, a fixed speed ratio for dressing specified, which is defined either as the ratio of the first speed to the second speed or as a ratio of the second speed to the first speed. Preferably, the value of the fixed speed ratio when dressing a natural Zah l corresponds to N. More preferably, the value of the fixed speed ratio of a natural number M of the set {1, 2, 3, 4 ... 10}.

However, embodiments are also possible, please include, where the fixed speed ratio during dressing is defined as a fraction of two natural numbers M. Particularly preferably, the value of the fixed speed ratio corresponds to a fraction of the quantity {Vi, 1/3, 2/3, ¹ A,%}.

In preferred embodiments, for a fixed speed ratio, a Exzenterverhältn is (usually from a number of several suitable eccentric ratios) determined and placed in the eccentric grinding of the bevel gear piece used. However, the use of such eccentric ratio is optional, but may serve to provide even better noise performance results.

The invention can be used above all for the fine or post-processing of bevel gear workpieces.

Further advantageous embodiments can be found in the dependent claims.

DRAWINGS

Exemplary embodiments of the invention will be described in more detail below with reference to the drawings.

FIG. 1 shows a schematic side view of a part of a

Grinding machine with a cup grinding wheel, which is dressed by means of a dressing wheel on the outer circumference (the dressing of the inner circumference with the dressing wheel is indicated in dashed lines representation);

FIG. 2 shows a highly schematic side view of a

Cup grinding wheel when plunge grinding a bevel gear workpiece, wherein the bevel gear is shown in Axialschn itt; FIG. FIG. 3A is a highly schematic, non-scale view of a cup grinding wheel eccentrically mounted on a wagon disc in a known manner and operating on the tooth gap of a crown wheel workpiece at the moment shown; FIG.

FIG. Fig. 3B is a highly schematic sectional view of the cup grinding wheel of Fig. 3A, taken along the line XI-XI;

FIG. 4A shows a highly schematic sectional view of a

Cup grinding wheel in radial section, which is dressed in the moment shown in a known manner with a dressing wheel on the outer circumference;

FIG. 4B shows a highly schematic side view of the cup grinding wheel of FIG. 4A after dressing with the dressing wheel of FIG. 4A at identical speeds;

FIG. 4C shows a highly schematic side view of the cup grinding wheel of FIG. 4A after dressing with the dressing wheel of FIG. 4A with uneven speeds;

FIG. Figure 5 shows a perspective view of an exemplary apparatus in which the method of the invention may be practiced.

Detailed description

In the context of the present description, terms are used which are also used in relevant publications and patents. It should be noted, however, that the use of these terms is for the convenience of understanding only. The inventive idea and the scope of the protection claims should not be limited by the specific choice of the terms in the interpretation. The invention can be readily applied to other conceptual systems and / or fields. In other fields the terms are to be applied analogously.

The invention is based on a holistic approach that optimizes the interaction of the dresser 30 during the dressing process with the cup grinding wheel 10 and the interaction of the appropriately trained Topfschleifscheibe 10 with the bevel gear 40, so indirectly affect the noise behavior of the bevel gear 40. The solution of the invention was possible only by a detailed analysis of the complex relationships and interdependencies. The results of these analyzes are explained below with the help of highly simplified examples and illustrations, before details of the solution according to the invention are described.

Reference will be made below, inter alia, to Figures 1, 2 and 3A and 3B and to the description thereof.

In Fig. 4A is a plan view of a cup grinding wheel 10 and a dressing wheel 30 is shown in a first, highly schematic snapshot. The profile 18 is shown only as a horizontal section (also called radial section). The dressing wheel 30 is shown as a disk whose diameter is here 50% of the outer diameter of the profile 18. Typically, the dressing wheel 30 has a diameter that is significantly smaller than the outside diameter of the cup grinding wheel 10. On the outer circumference of the dressing wheel 30, a fault F is shown by a small symbol. It can be z. B. may be a diamond crystal, which has a slightly different orientation from the other crystals. The dressing wheel 30 but z. B. also have a runout, the z. B. by a slight blow or stroke in the area of the symbol F can show. The principle described below applies both to dressing wheels 30 with flaws F of the surface, as well as for dressing wheels 30 with concentricity error.

When dressing one has always been given a speed ratio in order to achieve an optimal dressing result. The speed ratio is usually defined by the dressing factor. The dressing factor is defined as the ratio of dressing roll peripheral speed and peripheral wheel speed.

The rotational speed co3 of the dressing wheel 30 and the rotational speed col * of the cup grinding wheel 10 were controlled accordingly in order to achieve the desired relative cutting speed in the area of the instantaneous interaction. In the following, however, with the rotational speeds nl of the cup wheel 10 and n3 of the dressing wheel 30 is worked. The speeds are namely sizes that are independent of the radius or diameter.

If the two speeds match, i. E. if nl = n3, then the fault F or the concentricity error of the dressing wheel 30 touches the circumferential outer surface 18.1 only once per full revolution. If no other relative movements are carried out during dressing, this fault location F or the concentricity error would repeatedly hit the same point on the outer surface 18.1 of the cup grinding wheel 10.

FIG. 4B shows a side view of a cup grinding wheel 10 after dressing with a dressing wheel 30 of FIG. 4A. If the dressing wheel 30 is moved relative to the cup grinding wheel 10 during dressing relative to the direction of the axis of rotation Rl (paraxial feed advance called) and if the specification nl = n3 still applies, then there are a number of surface perturbations along an axis-parallel line. In Fig. 4B, the centers of these surface perturbations are represented by the dots of a dotted line 19.

If, as was previously the case, a suitable dressing factor for dressing based on a desired relative cutting speed, then there is almost always a speed ratio DV = nl / n3, which is not integer, since the dressing factor by the radii and by the respective angular velocities col and co3 of the cup wheel 10 and the dressing wheel 30 is determined. In practice, the speed ratio DV is therefore defined by an irrational number.

If one starts from a real cup wheel 10 whose side view is shown for example in Fig. 3B, then it should further be considered that the outer periphery is variable, since the profile 18 has a conical shape. Ie the effective effective diameter of the cup grinding wheel 10 and thus also the cutting speed change with the dressing feed. So if you want to maintain a certain relative cutting speed, as usual, you have to change the speed nl of the cup grinding wheel 10 and / or the speed n3 of the dressing wheel 30, while the dressing wheel 30 performs, for example, an axis-parallel dressing feed.

If one proceeds now from an irrational speed ratio nl / n3, which has always been the case in practice, and applying this to the example of Figures 4A, 4B, then it is immediately apparent that there is a complicated distribution of Surface defects on the peripheral outer surface 18.1 results. In Fig. 4C, such a distribution is symbolized in a simplified form by a plurality of surface perturbations which are distributed virtually arbitrarily on the outer surface 18.1. The surface defects are shown here schematically by several black dots.

In the following step, it is now assumed that a real dressing wheel 30 whose surface has not only a fault F but a whole number of faults and / or has a runout. These flaws can be e.g. be distributed along the circumference of the dressing wheel 30.

If a dressing of the outer surface 18.1 with irrational speed ratios nl / n3 is performed with a real dressing wheel 30, which has numerous defects and / or concentricity error, in which the dressing wheel 30 relative to the cup grinding wheel 10 an axially parallel dressing movement parallel to the direction the rotation axis Rl performs, then ultimately results in a random distribution of more or less strong surface defects on the entire outer surface 18.1. Similarly, when dressing the inner surface 18.2 also randomly distributed surface defects on the entire inner surface 18.2 occur.

In practice, these relationships are even more complicated than shown here. Therefore, 10 angle errors, crowning errors and ripples can result in the cup grinding wheel, the z. B. change along the circumference of the cup grinding wheel 10.

In the next step of thinking now the eccentric immersion machining of a bevel gear 40 is made with a real grinding cup 10, the outer surface 18.1 a random distribution of Has surface defects. Eccentric dipping is a discontinuous process in which bevel gear 40 does not rotate during grinding. When diving, only a relative Tiefenzustellung is made while the rotational movement col * of the cup grinding wheel 10 is superimposed on an eccentricity, as already described. A snapshot of an eccentric immersion machining is shown in FIG.

However, the method of the invention can also be applied to the eccentric Wälzschleifen. The eccentric Wälzschleifen is a discontinuous process in which tooth gap for tooth gap of the bevel gear 40 is processed. The rotational movement co2 * of the bevel gear workpiece 40 is coupled with the rotary movement col * of the top grinding wheel 10 during eccentric generating grinding.

When Wälzschleifen a line contact z. The rolling movement takes place during generating from the toothed tooth Zf (see FIG. 3A) at the outer diameter to the tooth toes Zz (see FIG. 3A) at the inner diameter of the bevel gear 40 or vice versa.

When generating rolling produced by the contact of bevel gear 40 and cup grinding wheel 10 a line of contact along the tooth flank, resulting in webs of the abrasive grains at the contact point or the Berührlinie arise. Due to the rolling motion, the position of this contact line changes constantly.

By superimposing an eccentric motion, the touch line is reduced to a point of contact that travels along the line of contact within an angular range of the eccentric rotation.

If, as described above, an eccentricity factor of, for example, 1 is specified, then there is one full turn of the cup grinding wheel 10 touching the outer surface 18.1 of the cup grinding wheel 10 with the concave edge 5.1 of the tooth gap 5 which has just been ground. Since the cup grinding wheel 10 is moved during grinding due to the coupled rolling movement through the tooth gap 5, while the cup grinding wheel 10 z. For example, five Performs full turns, there are five touches between the outer surface 18.1 of the cup grinding wheel 10 and the concave edge 5.1. Due to the mentioned rolling movement of the cup grinding wheel 10 through the tooth gap 5, the contacts wander along the concave edge 5.1, for example, from the tooth tip Zf to the tooth toe Zz.

Even if the surface perturbations on the outer surface 18.1 are randomly distributed, due to the integer eccentricity factor uniformly recurrent surface perturbations on the concave flank 5.1 are formed.

Investigations have shown that these evenly recurring surface defects can have a significant influence on the noise behavior of such bevel gear pieces 40. Occur with eccentrically submerged bevel gear pieces 40 e.g. Error in profile direction. In eccentric-beveled bevel gear pieces 40, depending on the grinding and Exzentspindeldrehzahl different wave patterns occur.

At this point, the invention begins. Facts were crystallized out which influence one another and which can ultimately lead to undesirable surface defects on the bevel gear workpiece 40.

In accordance with the invention, therefore, a special method has been developed to avoid causing surface perturbations that have a form of periodicity in an undesirable manner. Surface disturbances per se are inherent in the process, but it is possible, subject to certain preconditions, to prevent these surface disturbances from being unfavorably repeated or from being unfavorably superimposed on the workpiece in any other way.

The method of the invention is designed to be carried out in a grinding machine 100 (referred to generally herein as apparatus 100). The grinding machine 100 comprises, as shown by way of example in FIGS. 1 and 5, a tool spindle 11 for receiving and rotationally driving a cup grinding wheel 10 provided with abrasive surfaces 18. 1, 18. 2. In addition, it comprises a dressing spindle 31 for receiving and rotationally driving a dressing tool 30, which is designed to dress the cup grinding wheel 10. Furthermore, a workpiece spindle 41 is provided for receiving and rotationally driving a bevel gear workpiece 40, wherein the workpiece spindle 41 is provided with an eccentric drive 3, whose eccentric factor can be specified. The eccentric drive 3 can be designed, for example, as shown in Fig. 3A.

The method carried out in such a grinding machine 100 preferably comprises the following dressing steps in all embodiments:

Rotating the grinding wheel 10 about an axis of rotation R1 of the tool spindle 11 with a first (dressing) speed n1,

Rotational driving of the dressing tool 30 about a rotation axis R3 of the dressing spindle 31 with a second (dressing) rotational speed n3,

- Performing a dressing process in which the grinding wheel 10 is dressed with the dressing tool 30, wherein during this step between the first (dressing) speed nl and the second (dressing) speed n3 an exactly predetermined, fixed speed ratio DV is specified.

For this purpose, e.g. in all embodiments, a fixed speed ratio DV is defined, which is either defined as the ratio of the first speed n1 to the second speed n3 (i.e., DV = n1 / n3) or the ratio of the second speed to the first speed (i.e., DV = n3 / n1).

Preferably, the value of the fixed speed ratio DV corresponds to a natural number M. More preferably, the value of the fixed speed ratio DV corresponds to a natural number M of the set {1, 2, 3, 4 ... 10}.

However, embodiments are also possible in which the fixed speed ratio DV is defined as a fraction of two natural numbers M. Particularly preferably the value of the fixed speed ratio DV corresponding to a fraction of the set {Vi, 1/3, 2/3, ¹ A,%}.

By this first measure and by the described dressing steps with exactly predetermined, fixed speed ratio DV is causes no erratic, but a relatively g leichmäßige distribution of surface defects along the surfaces 18. 1, 18.2 of the cup grinding wheel 10 result. Thus, a round lauffeh ler the dressing wheel 30 forms exactly as round running error of the grinding wheel 10 (kinematic deviations from the dressing roller ius are neglected here) if z. B. from a Drehzahlverhältn isses DV = 1, 2 or z. B. Vi goes out.

Now, a so-honed cup grinding wheel 10 is used in the course of the following processing steps for grinding a bevel gear workpiece 40. These processing steps are carried out after performing the dressing steps.

Rotating the cup grinding wheel 10 about the rotation axis R 1 of the tool spindle 11,

- Carrying out an eccentric grinding process in which the bevel gear 40 is processed with the cup grinding wheel 10. Ie. it comes when grinding the bevel gear 40 always an eccentric 3 used.

During grinding of the bevel gear workpiece 40, an eccentric ratio EV is preferably set for the eccentric drive 3 in all embodiments, which is not very low.

When determining the eccentric ratio EV, as can be done in a part of the embodiments, it should be noted that this eccentric EV without relative (shift) movements between the cup grinding wheel 10 and the bevel gear 40 is defined. Other expressions, when determining an eccentric ratio EV, fluctuations in the eccentric ratio EV are not taken into account. B. from relative (shift) movements between the cup grinding wheel 10 and the bevel gear 40 result.

Particularly suitable are eccentric ratios EV, which correspond to no natural numbers. Ie. in the context of the invention, broken numbers are particularly suitable as eccentric factors EV. Alternatively, z. Belly Eccentric ratios are chosen which correspond to an even or odd natural number> 1 (eg 1, 2, 3, 4 or 5).

By means of this second optional measure, it is possible to ensure that there are no periodically repeating surface disturbances of the tooth flanks 5.1, 5.2 of the bevel gear workpiece 40. This is especially true for the eccentric Wälzschleifen of bevel gear 40 pieces.

An example device 100 is shown in FIG. 5 is shown. The method steps of the invention can be used in all embodiments, for. B. in a (machine) controller 120 of the device 100 to be implemented. However, the device 100 may be used in all embodiments e.g. also be controlled externally to carry out the steps of the method of the invention. In Fig. 5, the (machine) controller 120 is symbolized by an ellipse.

Particularly suitable is a device 100 with a workpiece spindle 41 for receiving a bevel gear workpiece 40 and a tool spindle 11 for receiving the cup grinding wheel 10. The device 100 has a plurality of drives for processing the bevel gear 40. The drives are hidden behind panels of the device 100. Furthermore, the device 100 shown by way of example comprises a machine bed 101. On a stand 102, which extends parallel to the x-y plane, a carriage 103 is provided, which is displaceable along horizontal rails 104 parallel to the Y-axis. The carriage 103 carries the tool spindle 11 and can perform translational movements in the X and Z directions.

The device 100 additionally comprises a dressing spindle 31 which carries a dressing wheel 30 here. The rotary drive, which causes the grinding wheel 10 to rotate about the rotation axis R1, is also referred to as Al rotary drive. A B-turn drive rotates the bevel gear 40 about the rotation axis R2. When grinding the bevel gear workpiece 40 with the cup grinding wheel 10, the rotational movements are (electronically) coupled. The corresponding drives of the device 100 are also designated here by the letters X, Y, Z, AI and B. The device 100 may additionally have a pivot axis C with a corresponding pivot drive, as shown in FIG. 5 shown. Reference number:

Wagon disc / eccentric 3

Area 4

Tooth gap 5

Concave tooth flank 5.1

Convex tooth flank 5.2

Grinding wheel / cup grinding wheel 10

Tool spindle 11

Area / profile 18 circumferential outer surface 18.1 circumferential inner surface 18.2

Line 19

Dressing tool / dressing wheel 30

Dressing spindle 31

Area / Profile 38

Bevel gear workpiece 40

Workpiece spindle 41

Device / 100

Machine / sander

Machine bed 101

Stand 102

Carriage 103

Rails 104

(Machine) control 120

Speed ratio DV

Distances

Eccentric Ratio EV

Fault location F

Center of the disc M l

Center point M2 natural numbers M

Speed nl

Processing speed nl *

Dressing speed n3 rational number Q

(Tool) rotation axis Rl

Dressing axis of rotation R3

Workpiece rotation axis R2

Angular velocity when dressing col

Angular velocity during col * edit Angular velocity during co2 * editing

Angular velocity during dressing

Coordinate system, y

Drives X, Y, Z, B, C, AI

Section XI - XI

Tooth horse Zf

Tooth toe Zz

Claims

claims

A method carried out in a grinding machine (100) comprising:

a tool spindle (11) for receiving a cup grinding wheel (10) provided with an abrasive surface (18.1, 18.2), and for rotationally driving the cup grinding wheel (10) about a rotation axis (R1),

a dressing spindle (31) for receiving a dressing tool (30) designed for dressing the cup grinding wheel (10) and for rotationally driving the dressing tool (30) about an axis of rotation (R3),

a workpiece spindle (41) for receiving a bevel gear workpiece (40) and for rotationally driving the bevel gear workpiece (40) about an axis of rotation (R2), the workpiece spindle (41) being provided with an eccentric drive (3),

with the following dressing steps:

a) rotationally driving the cup grinding wheel (10) about the rotation axis (R 1) of the tool spindle (11) at a first speed (n 1),

b) rotationally driving the dressing tool (30) about the axis of rotation (R3) of the dressing spindle (31) at a second rotational speed (n3),

c) Performing a dressing process in which the cup grinding wheel (10) is dressed with the dressing tool (30), wherein during this step, a predetermined, fixed speed ratio (DV) between the first speed (nl) and the second speed (n3) is specified , and with the following processing steps, which are carried out after the dressing steps have been carried out:

i. eccentric rotation driving the cup grinding wheel (10) about the rotation axis (Rl) of the tool spindle (11) with a first processing speed (nl *) using the eccentric drive (3), ii. Performing a grinding process in which the bevel gear workpiece (40) with the cup grinding wheel (10) is sanded.

2. The method according to claim 1, characterized in that at least during step c) a fixed speed ratio (DV) is specified, which is defined as the ratio of the first speed (nl) to the second speed (n3).

3. The method according to claim 1, characterized in that at least during step c) a fixed speed ratio (DV) is specified, which is defined as the ratio of the second speed (n3) to the first speed (nl).

4. The method according to claim 2 or 3, characterized in that the value of the fixed speed ratio (DV) corresponds to a natural number M.

5. The method according to claim 2 or 4, characterized in that the value of the fixed speed ratio (DV) as a fraction of two natural numbers M is defined.

6. The method according to any one of claims 1 to 5, characterized in that at least during step ii. an eccentric ratio (EV) of the

Eccentric drive (3) is set with a value corresponding to a rational number Q, if one does not take into account variations in the eccentric ratio (EV) resulting from relative shift movements between the cup grinding wheel (10) and the bevel gear workpiece (40).

7. The method according to any one of claims 1 to 5, characterized in that in step ii. the cup grinding wheel (10) carries out only relative relative movement to the bevel gear workpiece (40) in addition to the rotary driving of the cup grinding wheel (10).

8. The method according to any one of claims 1 to 5, characterized in that in step ii. the cup grinding wheel (10) performs a coupled rolling movement relative to the bevel gear workpiece (40) in addition to the rotary driving of the cup grinding wheel (10).

9. The method according to any one of claims 1 to 6, characterized in that in a preparatory method step, the speed ratio (DV) can be predetermined.

10. The method according to claim 9, characterized in that the predetermining the speed ratio (DV) by a prompt on a screen, which is connectable to the device (100).

11. The method according to claim 9, characterized in that the setting of the speed ratio (DV) via a controller (120) of the device (100).